The field of art to which this invention pertains is epoxy compounds and a process for reducing the amount of free epichlorohydrin in epoxy compounds.
The preparation of epoxy compounds by the reaction of epichlorohydrin with monocarboxylic or polycarboxylic acids, monohydric or polyhydric alcohols, and monohydric or polyhydric phenols is well known. Such compounds are usually prepared by reacting epichlorohydrin with an alcohol or acid to form a chlorohydrin ether or ester followed by the dehydrohalogenation of the ether or ester to form an epoxy compound. However, when a phenol is employed, the phenol is usually reacted with excess epichlorohydrin in the presence of sodium hydroxide so that condensation and dehydrohalogenation occurs concomitantly.
The employment of the prior art processes for preparing such epoxy compounds results in the presence of some free epichlorohydrin in the compounds, even though an attempt is usually made to reduce the amount of residual epichlorohydrin. The presence of free epichlorohydrin is undesirable because epichlorohydrin is toxic and is a contaminate in the compound. Generally, the prior art processes attempt to remove residual unreacted epichlorohydrin by distillation and/or by extraction with H.sub.2 O. See, for example, U.S. Pat. No. 3,859,314. However, the use of distillation, washing or other prior art means for reducing the amount of residual free epichlorohydrin still leaves relatively high amounts of free epichlorohydrin in the epoxy compound.
As a result, it is an object of this invention to reduce the amount of free epichlorohydrin in epoxy compounds.
It is another object of this invention to reduce the amount of free epichlorohydrin in epoxy compounds to a greater degree than is possible using the prior art methods for reducing free epichlorohydrin.
It is a further object of this invention to inexpensively and easily reduce the amount of residual epichlorohydrin in epoxy compounds.
These objects are obtained by the process of this invention.